Container



'L fill the groove in the other member, thus insur- 4Patented June 1 4,1938 i Y CONTAINER GeorgeArlington Moore, Louisville, Ky., assigner toHumoco Corporation, Louisville, Ky., a corporation of DelawareApplication August 22, 1935, Serial No. 37,284

2 Claims.

This invention relates to a method of making articles of fibrousmaterial, such as paper containers, and more particularly to a method ofuniting two or more brous or paper members to 5 make a joint or closureformation, and to the receptacle,- container, or other article producedby said method. v It has heretofore been proposed to join a side walland a anged end wall of a paper or paper-like article by inflowing saidside Wall by means of a flowing die, and then inflowing said wall andthe flange of said end wall, simultane-` ously, by means of a flowingdie of larger radius to form a triple-ply joint, the inflowed pliesbeing cradled or buried in a groove embossed in the end Wall to lock themultiple-ply folds in position and to completely fill said groove,Where- "by there is provided an air and moisture proof after in thedetailed description, which is to be joint..

' 2o In order to save material, among other reasons,

it is desirable to decrease to a minimum the number of folds of the sidewall and the flange of the end member but, as noted, this must be donewithout decreasing the bulk of the multiply folds to such an extent thatthe same will not completely ll the groove in the end wall. It isdesirable to make the groove of a minimum Width and to completely lillthis groove with a minimum number of folds of the side wall, but in manyinstances the width of this groove cannot Abe safely reduced to theequivalent of one thickness of the sidewall, for example, since fibrousor paper-1ike material will not safely withstand such excessivedeformation. Accordingly, one of the objects of the present invention Ais to provide a novel method for fabricating a.

jointor closure formation for paper or paperlike articles which willmeet the above requirements.

Another object of the invention is to provide a novel method offabricating a joint or closure formation of the class described,wherebycompensation is effected for variations in the dimensions of thestock used in making the joint. Other objects include the provision of amethod which will result in a saving of material, one which is adaptedfor forming articles and/or containers of various shapes and sizes, andone wherein a, hem may be formed in one of the joined members, said hembeing adapted yto completely ing that the'groove width' will be of asuitable dimensionwithout excessive stretching of the material in whichsaid groove is formed, and

that the hermetic qualities of the joint structur will be preserved.

A further object is to provide a. joint or closure formation formulti-part paper or paper-like articles wherein they raw edge of one ofthe parts, 5 as, for example, the top edge of the body portion, ispressed into a groove or recess in the adjoining member to prevent anyobjectionable effects which might otherwise arise from the hygroscopicaction of said raw edge. 10

Another object is to provide a novel welded joint structure for paper orsimilar articles which acts as a resilient cushion to resist distortionand to absorb stresses and strains, whereby the hermetic qualities ofthejoint structure are lat 15 ,all times preserved.

The above and other object's and advantages ofthe invention will appearmore fully hereinread in connection with the accompanying draw- 20 ingillustrating one manner of carrying out'the novel process, and also oneform of the resultant joint or closure formation. It is to be expresslyunderstood, however, that this drawing is for` the purpose ofillustration only, and that 25 reference is to be had primarily to theaccompanying claims for a definition of the limits of the invention. Inthe drawing, wherein like reference characters refer to like partsthroughout the several views: 30

Fig. 1 is a sectional View, with parts broken away, illustrating one ofthe steps in the process and one type of apparatus which may be employdin carrying out this step;

Fig. 2 is a view similar to Fig. l villustrating a 35 second step in theprocess;

Fig. 3 is a View similar to Figs. 1 and 2 illustrating a third step inthe process, and the joint or closure formation which is produced whenthe joined members are formed of one-ply stock; 40 and Fig. 4 is anenlarged sectional view, with parts broken away, illustrating one typeof joint which may be formed by uniting two laminated members inaccordance with theA method ofthe pres- 5 ent invention.

Referring more. particularly to Figs. 1 .to 3, inclusive, my novelmethod is illustrated in con- Y nection with the formation of a jointbetween the side and end walls 5 and 6, respectively, of a w paper orpaper-like container that is preferably, at least in part, ofarcuate'outline. As shown, the side walls of the article are deformed inany vsuitable manner well known in the art to provide an inner shoulder1 to receive the flanged end u member 6. The flange 8 of the latter anda groove 9 are preferably formed in the manner illustrated, describedand claimed in my Reissue Patent No. 19,504, dated March 19, 1935, saidange being connected to the central portion of end member 8 by thearcuate portion 9a.

The preformed shell 5 and head 6 are assembled in any suitable manner,as by hand or automatic machinery, and are then mounted on segments orjaws, one of which is shown in part at I0, said jaws being provided witha shoulder corresponding to the shoulder formed in side wall 5. Astationary die bolster II, having an inner diameter equal tothe outerdiameter or dimension of the side walls 5, is mounted in any suitablemanner above segments l0 and preferably in engagement therewith. Asshown, bolster II carries a heating element I2 of any suitable type,such as electrical, gas or steam, the .heating of the fibrous stockfacilitating the carrying out of the operation. Slidably mounted withindie bolster I I is a flowing die I3 which is provided with acircumferentially extending, endless, arcuate groove I4 and anoverhanging lip I5, the outer wall of said lip merging into the arcuatesurface of groove Il.

Preferably, the groove Id is inclined to the horizontal a small amount,as, for example, two or more degrees, the inclination being shownexaggerated at Ila in Fig. l. By this meansthe flowing die I3 engages aportion only of the upper edge of side wall 5 when first moved into en.gagement therewith so that said upper edge is progressively curledinwardly. v

When flowing die I3 is moved downwardly from the dotted-line position ofFig. l to the full line position, the upper edgeof side wall 5, which isshown in section at 5a by means of dotted lines, is flowed downwardly,forming a curl of a small radius. Die I3 is now removed, and a plug I6(Fig. 2) is inserted within the bolster, and moved into and held inengagement with the upper surface of member 6,the outer wall of saidplug conforming to shoulderla of said member. A flowing die II is nowinserted between plug I6 and bolster II, the lower edge I'Ia of saidflowing die being arcuate and having approximately twice the radius ofcurvature of the arcuate portion I4 of flowing die I3. is moveddownwardly, the arcuate surface Ila progressively engages the uppercurled edge of side wall 5 and continues the curling operation, thedownward pressure on lmember I'I being continue-d until the curled edgeof wall 5 is forced to the bottom'of groove 9 in member 6.

The operative surface of groove I'Ia is per-v pendicular to the innerlateral wall f bolster Ii so that compensation is effected for the biasopposed on the upper edge of side wall 5 by the inclined groove I4 offlowing die I3. During the above operations, bolster Il is maintainedheated by the element I2.

Plug I6 and flowing die Il are now removed,

'and a die I8 (Fig. 3) is inserted withinI the When flowing die I'Igroove. 'Ihe portion ofthe side wall intermediate die I8 and hem I9tends to bow inwardly, and sufficient pressure is placed on said die toforce the side wall directly into engagement with the upper side offlange 8.

Expandible segments 20 .are now inserted within die I8 and moveddownwardly until they engage the upper surface of end member 6,whereupon said segments are expanded or moved outwardly compressing theinner verticalleg or bowed portion of the side wall, with the resultthat the excess material is forced outwardly and downwardly, furthercompacting the lfibers in groove 8 so that said groove is completelyfilled and the raw edge of hem I9 is buried in said groove so that itshygroscopic qualities, as well as those of the raw edge of flange 8, are'rendered ineffective to destroy theimperviousness of the joint orclosure formation. Pressure is retained on die IB during the outwardmovement of segments 28.

Preferably, the inner surface of side wall 5, or at least that portionthereof including shoulder I and the inner surface above said shoulder,or, if desired, the inner and outer surface of flange 8, or of both theside wall and the flange, has disposed thereon a thin thermoplastic filmwhich isY moisture proof but which may be activated by the heat ofelement I2 to render the same tacky. Accordingly, when members I8 and.2U are moved to the positions shown in Fig. 3,

sufficient pressure will be exerted on the contacting surfaces oftheflange and side wall to weld these surfaces, whereby a hermetic joint isformed. A

The thermoplastic film preferably comprises a 'nitrocellulosic basehaving incorporated therein -properly proportioned amounts of resins andplasticizer 'for suitable heat activation, as the film, substantiallyfree from brittleness and free from tack, at the low temperaturesemployed in the fabrication of the container. When activated by heat athigher temperatures, it softens without tending lto flow to an extentwhich would cause the dissipation thereoffas a film.y and render thefilm unavailable for welding parts together. Preferably, a lacquer isemployed which will be activated at a temperature of 150 to 2009Fahrenheit. A portion of the welded joint'formed by the process of thisinvention is illustrated at 2l by means of short horizontally disposedhatching lines.

In Fig. 4 there is illustrated a joint or ,closure formation of thecharacter produced by the present method when the joined members arelaminated or formed of multi-ply stock. The two-ply side wall 22 isjoined to a three-ply end member or head 23. The upper or outer ply 23aof head 23 may be formed of thin metal, such as foils of aluminum orlead, while the two inner plies 23h are formed of paper or fiber. Thehem 24 of the inflowed portion and the upper edge 25 ofthe flange of theend member are buried within the joint, preventing any tendencyl ofthese portions to absorb moisture. 'I'he ihflowed portion of the sidelwall within the groove of the head is materially compacted but is stillsufliciently resilient to resist stresses and strains on the joint whilesaid compacted portion and the ment, and a joint which is impervious toair and arcuate wall of the groove are effective to resist distortion.It will be noted that expandible segments 20, employed-in forming thejointl of Fig. 4, are not 'moved directly into engagement with the outersurface of end member 23, whereby an arcuate bead 26 is produced in sidewall 22 im- .-mediately above the grooveL I'he disclosed method offorming a joint or closure formation is such that greater tolerances inthe over-alldimensions of members and 6, 22 and 23 are allowable withoutproducing any objectionable effects in the joint formed.` This resultsfrom the fact that any variations in dimensions will be compensated forin the hem and in the compacted portions within the groove in the endmember.

'I'he provision of the hem in the side wall provides for two thicknessesof: material in the groove, thus reducing the extent of the foldrequired to fill said groove and avoiding any necessity for providing agroove of such small Width as to unduly stress or strain the material ofend member 6 or 23.

There is thus provided a novel method which may be carried out partly byhand or may be carried out by fully automatic machinery. The

method is simple and inexpensive and lends itself to quantity productionand saving of material. The joint .or closure formation produced by themethod constitutes a resilient cushion adapted to absorb stresses orstrains imposed on the end or side wall members. The folds of the sidewall are buried in a deformation groove whereby the same are lockedagainst horizontal movemoisture is secured.

What is claimed is:

1. The method of forming a joint between a flanged and grooved endmember and a side wall member having an inwardly directed shoulder whichconsists in placing said end memberin engagement with said shoulder,infiowing the marginal edge of said side wall member to provide a curl,inflowing said side wall and curl into said groove, applyinglongitudinal pressure to the infiowed portion of the side wall to pressthe same into engagement with the upper edge of said ange and to bottomsaid curl in the groove,

and applying radial pressure to said flange and `iniiowed side wallportion to completely fill said groove and lock said `iniiowed portionagainst lateral movement.

2. The method of making a container which comprises inserting aflangedhead having a peripheral groove therein within a tubular body, curlingthe marginal edge of said body upon a radius to form a curl, flowing themarginal portion of said body upon a relatively wider radius than saidfirst-named radius while guiding said curl into said groove, applyinglongitudinal pressure to the iniiowed portion to press the same intoengagement with the upper edge of said flange and-to bottom said curl insaid groove, and applying radial-pressure to said flange and iniiowedportion to. completely 'lll said groove and lock said inflowed portionagainst radial movement.

GEORGE ARLINGTON MOORE.

